ModemManager: [PATCH 0/2] Improvements to SIM PIN handling

[Eric Shienbrood <ers google com>]

This is a follow-up to a patch I sent in July, and the ensuing discussion (which can be seen here: http://mail.gnome.org/archives/networkmanager-list/2011-July/msg00072.html). There are now two patches:

• The first correctly tracks the number of PIN retries left following EnablePin and ChangePin operations
• The second defines a new property that is a bit field indicating which facility locks are enabled. Facility locks include SIM PIN, SIM PIN2, several personalization options (e.g,. to lock a SIM to a specific network or service provider), and a set of call barring options. The call barring options are not represented in the new property.

In the original discussion, we talked about maintaining a dictionary to keep track of retry count and {enabled/disabled} state for every facility. This would have been a lot of complexity for what would be of dubious benefit. Users really only care about the retry count, for the specific PIN they're trying to, or about to, enter. This is what the existing UnlockRetries property keeps track of, and I believe it's sufficient. What was missing was a way to tell which locks were enabled, so that, e.g., a UI could display a check box for enabling or disabling the lock, and initialize the check box to the correct state.

With this change, at modem initialization time the set of supported facilities is determined, and then, for each supported facility, its state is queried. The results are stored in the property "EnabledFacilityLocks" on the Modem.Gsm.Card interface. This property is updated when the state of a facility lock is changed.

Eric